Adhesion of glass ionomer cements to primary dentin using a universal adhesive.

BACKGROUND: Glass ionomers are widely used for restoring carious primary teeth. However, their ability to bond to primary dentin is considered a challenge in pediatric dentistry. OBJECTIVES: The study aimed to evaluate the microshear bond strength (µSBS) of a resin-modified glass ionomer (RMGI) and a high-viscosity glass ionomer cement (Hv-GIC) to primary dentin using a universal adhesive. MATERIAL AND METHODS: Thirty human primary maxillary canines were cut in half and prepared for the µSBS test. The specimens (N = 60) were assigned to 6 groups. Three groups were defined for RMGI (FUJI II LC) and 3 groups for Hv-GIC (EQUIA Forte): with an immediately curing adhesive (G-Premio); with a delayed curing adhesive; and without an adhesive (control group). After preparing the dentin surfaces, the glass ionomers were bonded using Tygon® tubes with an internal diameter of 0.7 mm. The µSBS test was performed, and the data was analyzed using two-way analysis of variance (ANOVA) followed by Tukey's post hoc test. Additionally, the failure modes were determined using a stereomicroscope. Six specimens, one for each study group, were prepared for scanning electron microscopy (SEM) analysis to observe the glass ionomer-dentin interface. RESULTS: The type of glass ionomer did not have a significant effect on the µSBS (p = 0.305). Groups that received universal adhesive application prior to glass ionomer exhibited a significantly higher µSBS (p < 0.0001). However, there was no significant difference between the immediately curing and delayed curing groups (p = 0.157). The predominant failure mode was mixed failure. CONCLUSIONS: Higher bond strength of glass ionomers to primary teeth can be achieved by using universal adhesives, which, in addition to the proven benefits of glass ionomers, can improve their clinical success.

Relationship between the salivary concentrations of proteinase-3 and interleukin-8 and severe early childhood caries.

BACKGROUND: Severe early childhood caries (S-ECC) is a multifactorial transmissible infectious disease continuing to affect infants and toddlers worldwide. Saliva plays a modulatory role in the pathogenesis of dental caries. OBJECTIVES: The present study aimed to assess the salivary levels of proteinase-3 (PR3) and interleukin-8 (IL-8) as pro-inflammatory cytokines related to the function of neutrophils in association with S-ECC and its treatment. MATERIAL AND METHODS: Fifty children aged 36-60 months were recruited (25 caries-free controls and 25 S-ECC patients). Saliva sampling was performed in all participants. In the S-ECC group, sampling was repeated 6-8 weeks after restorative treatment. The salivary concentrations of PR3 and IL-8 were determined using the enzyme-linked immunosorbent assay (ELISA). The χ2 test, Fisher's exact test, the independent t test, and the paired t test were applied at p < 0.05. RESULTS: The baseline salivary concentrations of PR3 and IL-8 in the S-ECC group were significantly higher than in the caries-free group (p < 0.001). A significant reduction occurred in the levels of these cytokines following restorative treatment in the S-ECC group (p < 0.001), although they were still significantly higher than in the caries-free group (p < 0.05). CONCLUSIONS: The salivary levels of PR3 and IL-8 were significantly affected by the presence of dental caries in children, implying their potential efficiency as non-invasive indicators in the determination of the caries risk and treatment effectiveness.

Relationship between the salivary concentration of matrix metalloproteinases 8 and 20 and severe early childhood caries.

BACKGROUND: Dental caries is initiated through mineral dissolution by bacterial acids and collagen degradation by endogenous proteolytic enzymes, mainly collagenolytic matrix metalloproteinases (MMPs). OBJECTIVES: The present research aimed to evaluate the relationship between severe early childhood caries (S-ECC) and salivary MMP-8 and MMP-20 concentrations. MATERIAL AND METHODS: Fifty children aged 36-60 months were assigned to either the caries-free (control) group or the S-ECC group. Standard clinical examinations were performed, and approx. 1 mL of expectorated unstimulated whole saliva was collected from all participants. In the S-ECC group, the sampling was repeated 3 months after restorative treatment. All samples were analyzed for the salivary concentrations of MMP-8 and MMP-20, using the enzyme-linked immunosorbent assay (ELISA). Statistical analysis employed the t test, the Mann-Whitney U test, the χ2 test, Fisher's exact test, and the paired samples t test. The level of significance was set at 0.05. RESULTS: At baseline, the subjects in the S-ECC group presented with significantly elevated levels of MMP-8 as compared to the control group. However, the salivary concentration of MMP-20 did not exhibit a significant difference between the 2 groups. A significant reduction occurred in the levels of MMP-8 and MMP-20 3 months after restorative treatment in the S-ECC group. CONCLUSIONS: The salivary levels of MMP-8 and MMP-20 were significantly affected by dental restorative treatment in children. Furthermore, MMP-8 was observed to be a better indicator of the dental caries status than MMP-20.

Relationship of Vitamin D Deficiency with Cervical Vertebral Maturation and Dental Age in Adolescents: A Cross-Sectional Study.

Background: Considering the high prevalence of vitamin D deficiency and its effect on growth and development, the assessment of the dental age and skeletal age with regard to vitamin D deficiency status could influence the treatment planning of growth modification treatment. This study aimed to assess the relationship between vitamin D deficiency, cervical vertebral maturation (CVM) as an indicator of skeletal age, and dental age in adolescent patients. Methods: In this cross-sectional study, the chronological age of 52 orthodontic patients aged between 10 and 14 years was recorded, and their serum level of vitamin D was determined using a radioimmunoassay test. The patients were then divided into three groups based on their serum vitamin D level: severe deficiency, moderate deficiency, and the control group with normal vitamin D. The panoramic radiographs of patients were assessed to determine their dental age using Demirjian's method. CVM was determined on lateral cephalograms using Baccetti's classification to specify the skeletal age. Data were analyzed using a t-test, linear regression, ordinal logistic regression, and Pearson's correlation coefficient (at P < 0.05, confidence interval = 95%). Results: Skeletal age showed a significant difference between the group with severe vitamin D deficiency and the control group (P=0.01); however, such difference was not observed between the group with moderate vitamin D deficiency and the control group (P=0.12). Dental age was not significantly different between the groups with vitamin D deficiency and the control group (P=0.26 for severe, and P=0.39 for moderate deficiency). Conclusions: A less advanced skeletal maturation was observed in adolescents with severe vitamin D deficiency; however, dental development was not affected by this deficiency. Vitamin D status is better to be considered in decision-making for the initiation of growth modification orthodontic treatments.

Antibacterial effect of an herbal toothpaste containing Bamboo salt: a randomized double-blinded controlled clinical trial.

BACKGROUND: The inclusion of herbal antibacterial agents in the composition of toothpastes is becoming increasingly popular, due to lower side effects. The present study intended to investigate the antibacterial efficacy of a herbal toothpaste containing Bamboo salt on cariogenic oral bacteria. METHODS: The present double-blinded parallel randomized controlled clinical trial was conducted on 60 dental students (age range: 18-30). Following the baseline saliva sampling, the participants were randomly assigned into the case and control groups, to use the Bamboo salt herbal toothpaste and conventional non-herbal toothpaste, respectively. They were instructed to brush their teeth twice a day using the Bass technique. Saliva sampling was repeated after four weeks. The salivary counts of Streptococcus mutans and Lactobacillus at baseline and 4-week follow-up were determined and presented as the logarithm of colony-forming units per milliliter (log CFU/mL). RESULTS: A significant decrease in salivary Streptococcus mutans and Lactobacillus was observed using both toothpastes (*P < 0.001). The difference between the antibacterial efficacy of two toothpaste types on Streptococcus mutans and Lactobacillus was not statistically significant (P = 0.530, and P = 0.137, respectively). CONCLUSION: Due to the comparable efficacy of the investigated herbal toothpaste with conventional toothpaste, it potentially qualifies as a complementary agent for self-care oral hygiene procedures. TRIAL REGISTRATION: This trial was registered in the "Iranian Registry of Clinical Trials" (IRCT20210414050964N1) on 21/06/2021.

Effect of Enamel Pretreatment Using Er,Cr:YSGG Laser Irradiation on Micro-shear Bond Strength of a Self-etch Fissure Sealant.

Fissure sealant application is an efficient method for dental caries prevention. Self-etch fissure sealants (SE-FS) eliminate the separate etching step for bonding. The present study investigated the micro-shear bond strength (µSBS) of a SE-FS (Prevent seal®, Itena©, Paris, France) to enamel pretreated with different methods including Er,Cr:YSGG laser, under noncontaminated and saliva-contaminated conditions. Sixty human premolars were sectioned into halves and randomly assigned into two groups of saliva-contaminated and noncontaminated. Each group was further divided into six subgroups (N = 10) of different enamel pretreatment methods: (Laser+SE-FS), (Acid-etch+SE-FS), (Laser+Acid-etch+SE-FS), (Mechanical preparation+SE-FS), (SE-FS), and (Acid-etch+Bonding+Conventional fissure sealant) as positive control. The µSBS of the sealant material to enamel was measured in all subgroups. The two-way ANOVA and Tukey tests were applied at P < 0.05. Saliva contamination had a significant effect on µSBS (P < 0.001), while pretreatment with laser or acid etching did not significantly affect the µSBS (P = 0.251). The µSBS of SE-FS to untreated enamel surface was significantly lower than the positive control (P = 0.035). The µSBS value in the subgroup receiving laser+etching+SE-FS was significantly higher than the remaining five subgroups (P < 0.001). Other pairwise comparisons were not statistically significant (P > 0.05). Acid-etch and Er,Cr:YSGG laser exert a synergic effect on µSBS of Prevent Seal®, irrespective of saliva contamination.

In Vitro Effects of Three Fluoride-Free Pastes on Remineralization of Initial Enamel Carious Lesions.

Purpose: The purpose of this study was to compare the efficacy of nanohydroxyapatite (NHA), casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), and calcium sodium phosphosilicate (NovaMin®) in remineralization of early enamel lesions and compare enamel surface changes using a scanning electron microscope (SEM). Methods: Thirty human premolars were sectioned into halves and randomly assigned to five groups (control, demineralization, NHA, CPP-ACP, NovaMin®; n equals 12). Ten samples in each of the three test groups were demineralized and treated with their designated paste for two minutes in 24-hour intervals for 30 days. They were subjected to the Vickers microhardness test on days 15 and 30, and their microhardness values were compared to the control and demineralization groups. The remaining two samples of each group were observed through SEM. Analysis of variance, Tukey's test, and paired t-tests were applied at P<0.05. Results: On day 15, a significant increase in surface microhardness compared to the control was only observed in the CPP-ACP group (P<0.05). Microhardness scores of all paste groups significantly increased between days 15 and 30 (P<0.001), while no significant differences were observed between them on day 30. In SEM images of all test groups, surface integrity increased, although NHA-treated samples had the most homogenous surface. Conclusion: Since all three pastes significantly remineralized incipient enamel lesions, they are potentially qualified for caries prevention.